A great number of foods, drinks, pharmaceuticals for oral administration, toiletries which have a bitter taste are known. Particularly, most of pharmaceuticals have a bitter taste, and some difficulty or pain arises when such pharmaceuticals are orally administered. Accordingly, suppression of a bitter taste of pharmaceuticals have been problems to be solved. Until now, the following methods have been known. Typically, addition of a sweetener or flavor has been employed. Japanese Patent Provisional Publication No. 2-56416 discloses addition of aspartame to pharmaceuticals, Also known are microcapsulation and coating using material soluble in stomach. Further known is chemical modification of a pharmaceutically active component. Japanese Patent Provisional Publication discloses use of a clathrate compound. These methods are employable only for specific compounds or the suppression of a bitter taste accomplished by these method appears insufficient.
For the suppression of a bitter taste in pharmaceuticals, the addition of a lipid is also known. For instance, Japanese Patent Publication No. 55-8966 discloses addition of lecithin (phosphatidylcholine) and cephalin singly or in combination. Japanese Patent Provisional Publication No. 62-265234 discloses addition of lecithin (phosphatidylcholine). These methods, however, are still insufficient to give the desired suppression of a bitter taste.
Infants and aged persons sometimes reject oral administration of solid pharmaceutical preparations. For this reason, syrup preparations are frequently employed. However, no appropriate methods to suppress a bitter taste of syrup preparations have been known.
In foods and drinks, there are certain bitter substances. For instance, bitter tastes of amino acids prepared by decomposition of proteins, bitter tastes of peptides, bitter taste of fruit or vegetable juices, and bitter tastes originating from flavor are mentioned. The presence of such bitter substances in foods and drinks sometimes lower quality of these foods and drinks. Removal of bitter tastes from foods and drinks have been reported as follows. Japanese Patent Provisional Publication No. 55-108254 proposes the use of an absorbent material, Japanese Patent Provisional Publication No. 61-40260 proposes the use of a clathrate confound, and Japanese Patent Provisional Publication describes addition of a sweetener. These methods, however, sometimes inappropriate, because the suppression of a bitter taste is not enough, or the addition of such compound alters taste of foods or drinks.
The problems of a bitter taste also resides in toiletries for the use on face and in mouth, such as lotions, mouthwashes and tooth pastes. For instance, surface active agents or flavors sometimes give bitter tastes. Therefore, the addition amount of surface active agents or flavors is sometimes limited. Until now, such bitter tastes have been masked by the use of sweeteners or specific flavors. However, such methods are not effective, if greatly bitter substances are involved.